If you have up to 28 weeks of pregnancy, without complications, you can travel without medical documents.
Between 28 and 36 weeks of pregnancy it`s necessary to present a medical certificate, stating the expected date of birth, the confirmation that the pregnancy is without complications, and that you are fit to travel by plane. The certificate needs to be signed and stamped by your doctor.
If you exceeded 36 weeks in case of singular pregnancies or 32 weeks in case of twin/multiple pregnancies, you are no longer accepted for travel.
You can fly 48 hours after giving birth only if the birth was without complications and didn’t require a surgical intervention. If the birth required surgical intervention you need to wait a minimum of 10 days from the intervention; a fit to fly medical document is also required.